Headings docs: use put <hN>s within <td>s instead of <th>s

assets/css/docs.css

@@ -414,17 +414,15 @@ body {
 }
 
 /* Typography */
-.bs-example-type .table td {
+.bs-example-type .table td:last-child {
   color: #999;
   vertical-align: middle;
 }
-.bs-example-type .table td,
-.bs-example-type .table th {
+.bs-example-type .table td {
   padding: 15px 0;
   border-color: #eee;
 }
-.bs-example-type .table tr:first-child td,
-.bs-example-type .table tr:first-child th {
+.bs-example-type .table tr:first-child td {
   border-top: 0;
 }
 .bs-example-type h1,

css.html

@@ -585,27 +585,27 @@ base_url: "../"
       <table class="table">
         <tbody>
           <tr>
-            <th><h1>Bootstrap heading</h1></th>
+            <td><h1>Bootstrap heading</h1></td>
             <td>Semibold 38px</td>
           </tr>
           <tr>
-            <th><h2>Bootstrap heading</h2></th>
+            <td><h2>Bootstrap heading</h2></td>
             <td>Semibold 32px</td>
           </tr>
           <tr>
-            <th><h3>Bootstrap heading</h3></th>
+            <td><h3>Bootstrap heading</h3></td>
             <td>Semibold 24px</td>
           </tr>
           <tr>
-            <th><h4>Bootstrap heading</h4></th>
+            <td><h4>Bootstrap heading</h4></td>
             <td>Semibold 18px</td>
           </tr>
           <tr>
-            <th><h5>Bootstrap heading</h5></th>
+            <td><h5>Bootstrap heading</h5></td>
             <td>Semibold 16px</td>
           </tr>
           <tr>
-            <th><h6>Bootstrap heading</h6></th>
+            <td><h6>Bootstrap heading</h6></td>
             <td>Semibold 12px</td>
           </tr>
         </tbody>